energy.json

{"nodes":[
{"name":"Agricultural 'waste'"},
{"name":"Bio-conversion"},
{"name":"Liquid"},
{"name":"Losses"},
{"name":"Solid"},
{"name":"Gas"},
{"name":"Biofuel imports"},
{"name":"Biomass imports"},
{"name":"Coal imports"},
{"name":"Coal"},
{"name":"Coal reserves"},
{"name":"District heating"},
{"name":"Industry"},
{"name":"Heating and cooling - commercial"},
{"name":"Heating and cooling - homes"},
{"name":"Electricity grid"},
{"name":"Over generation / exports"},
{"name":"H2 conversion"},
{"name":"Road transport"},
{"name":"Agriculture"},
{"name":"Rail transport"},
{"name":"Lighting & appliances - commercial"},
{"name":"Lighting & appliances - homes"},
{"name":"Gas imports"},
{"name":"Ngas"},
{"name":"Gas reserves"},
{"name":"Thermal generation"},
{"name":"Geothermal"},
{"name":"H2"},
{"name":"Hydro"},
{"name":"International shipping"},
{"name":"Domestic aviation"},
{"name":"International aviation"},
{"name":"National navigation"},
{"name":"Marine algae"},
{"name":"Nuclear"},
{"name":"Oil imports"},
{"name":"Oil"},
{"name":"Oil reserves"},
{"name":"Other waste"},
{"name":"Pumped heat"},
{"name":"Solar PV"},
{"name":"Solar Thermal"},
{"name":"Solar"},
{"name":"Tidal"},
{"name":"UK land based bioenergy"},
{"name":"Wave"},
{"name":"Wind"}
],
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{"source":8,"target":9,"value":11.606},
{"source":10,"target":9,"value":63.965},
{"source":9,"target":4,"value":75.571},
{"source":11,"target":12,"value":10.639},
{"source":11,"target":13,"value":22.505},
{"source":11,"target":14,"value":46.184},
{"source":15,"target":16,"value":104.453},
{"source":15,"target":14,"value":113.726},
{"source":15,"target":17,"value":27.14},
{"source":15,"target":12,"value":342.165},
{"source":15,"target":18,"value":37.797},
{"source":15,"target":19,"value":4.412},
{"source":15,"target":13,"value":40.858},
{"source":15,"target":3,"value":56.691},
{"source":15,"target":20,"value":7.863},
{"source":15,"target":21,"value":90.008},
{"source":15,"target":22,"value":93.494},
{"source":23,"target":24,"value":40.719},
{"source":25,"target":24,"value":82.233},
{"source":5,"target":13,"value":0.129},
{"source":5,"target":3,"value":1.401},
{"source":5,"target":26,"value":151.891},
{"source":5,"target":19,"value":2.096},
{"source":5,"target":12,"value":48.58},
{"source":27,"target":15,"value":7.013},
{"source":17,"target":28,"value":20.897},
{"source":17,"target":3,"value":6.242},
{"source":28,"target":18,"value":20.897},
{"source":29,"target":15,"value":6.995},
{"source":2,"target":12,"value":121.066},
{"source":2,"target":30,"value":128.69},
{"source":2,"target":18,"value":135.835},
{"source":2,"target":31,"value":14.458},
{"source":2,"target":32,"value":206.267},
{"source":2,"target":19,"value":3.64},
{"source":2,"target":33,"value":33.218},
{"source":2,"target":20,"value":4.413},
{"source":34,"target":1,"value":4.375},
{"source":24,"target":5,"value":122.952},
{"source":35,"target":26,"value":839.978},
{"source":36,"target":37,"value":504.287},
{"source":38,"target":37,"value":107.703},
{"source":37,"target":2,"value":611.99},
{"source":39,"target":4,"value":56.587},
{"source":39,"target":1,"value":77.81},
{"source":40,"target":14,"value":193.026},
{"source":40,"target":13,"value":70.672},
{"source":41,"target":15,"value":59.901},
{"source":42,"target":14,"value":19.263},
{"source":43,"target":42,"value":19.263},
{"source":43,"target":41,"value":59.901},
{"source":4,"target":19,"value":0.882},
{"source":4,"target":26,"value":400.12},
{"source":4,"target":12,"value":46.477},
{"source":26,"target":15,"value":525.531},
{"source":26,"target":3,"value":787.129},
{"source":26,"target":11,"value":79.329},
{"source":44,"target":15,"value":9.452},
{"source":45,"target":1,"value":182.01},
{"source":46,"target":15,"value":19.013},
{"source":47,"target":15,"value":289.366}
]}

index.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Sankey Diagram</title>
<style>

@import url(http://bost.ocks.org/mike/style.css?20120521);

#chart {
  height: 500px;
}

.node rect {
  cursor: move;
  fill-opacity: .9;
  shape-rendering: crispEdges;
}

.node text {
  pointer-events: none;
  text-shadow: 0 1px 0 #fff;
}

.link {
  fill: none;
  stroke: #000;
  stroke-opacity: .2;
}

.link:hover {
  stroke-opacity: .5;
}

</style>
<body>

<h1>Sankey Diagrams</h1>

<p id="chart">

<script src="http://d3js.org/d3.v2.min.js?2.9.1"></script>
<script src="https://raw.github.com/kunalb/d3-plugins/sankey/sankey/sankey.js"></script>
<script>

var margin = {top: 1, right: 1, bottom: 6, left: 1},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var formatNumber = d3.format(",.0f"),
    format = function(d) { return formatNumber(d) + " TWh"; },
    color = d3.scale.category20();

var svg = d3.select("#chart").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
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var sankey = d3.sankey()
    .nodeWidth(15)
    .nodePadding(10)
    .size([width, height]);

var path = sankey.link();

d3.json("energy.json", function(energy) {

  sankey
      .nodes(energy.nodes)
      .links(energy.links)
      .layout(32);

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      .data(energy.links)
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      .attr("class", "link")
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      .style("stroke-width", function(d) { return Math.max(1, d.dy); })
      .sort(function(a, b) { return b.dy - a.dy; });

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      .text(function(d) { return d.source.name + " → " + d.target.name + "\n" + format(d.value); });

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      .data(energy.nodes)
    .enter().append("g")
      .attr("class", "node")
      .attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; })
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      .origin(function(d) { return d; })
      .on("dragstart", function() { this.parentNode.appendChild(this); })
      .on("drag", dragmove));

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      .attr("width", sankey.nodeWidth())
      .style("fill", function(d) { return d.color = color(d.name.replace(/ .*/, "")); })
      .style("stroke", function(d) { return d3.rgb(d.color).darker(2); })
    .append("title")
      .text(function(d) { return d.name + "\n" + format(d.value); });

  node.append("text")
      .attr("x", -6)
      .attr("y", function(d) { return d.dy / 2; })
      .attr("dy", ".35em")
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      .attr("transform", null)
      .text(function(d) { return d.name; })
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    link.attr("d", path);
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});

</script>